policy: factor out duplicate regex string into variable
policy: factor out duplicate regex string into variable

Signed-off by: Ian Vernon <ian@cilium.io>

michi-covalent/cilium,cilium-team/cilium,tklauser/cilium,tgraf/cilium,cilium/cilium,cilium/cilium,tklauser/cilium,michi-covalent/cilium,tklauser/cilium,tgraf/cilium,michi-covalent/cilium,michi-covalent/cilium,cilium-team/cilium,cilium/cilium,tgraf/cilium,tklauser/cilium,michi-covalent/cilium,cilium/cilium,tklauser/cilium,tgraf/cilium,cilium/cilium,tgraf/cilium,tgraf/cilium